Steam for Linux

Running a dual monitor system, primary is 1680x1050 (lower right), secondary is 1440x900 (upper left). Starting TF2 always opens on the secondary (1440x900). In addition, the mouse isn't quite aligned with the menu item it's selecting, with lower and rightmost parts of the menu being the worst aligned (to the point that I cannot quit properly because I cannot bring my mouse past the bottom of my screen to have the "Quit" item highlighted). I suspect the game is displaying on 1440x900 but using 1680x1050 for its "true mouse positioning".

Just to pipe in. I'm seeing something like this too. The grey starting background image seems like it expects a wider monitor, so it looks cropped. I have the same mouse issue, The cursor is quite much below where the menu thinks it is.